reproductive system Flashcards
What are the four main functions of the reproductive system?
- Form gametes
- Bring male and female gametes together
- Combine the genetic information of gametes
- Support the development of the foetus and parturition
What does the HPG axis stand for?
Hypothalamus, Anterior pituitary, and gonads
What are the main sex hormones in males and females?
- Testosterone (male)
- Prostaglandin (female)
- Oestrogen (female)
What is puberty?
Time when sexual maturation is achieved
True or False: Before puberty, circulating sex hormone levels are high.
False
What is gender dysphoria?
A sense of unease due to a mismatch between biological sex and gender identity
What treatments may individuals with gender dysphoria pursue?
- Acceptance and affirmation
- Voice changes
- Hormone treatment
- Surgery
What are the primary sex organs in males?
Testes
What are the accessory reproductive organs in the male reproductive system?
- Ducts
- Glands
- External genitalia
What is the function of the scrotum?
Contains the testes and regulates their temperature
What is the normal temperature required for sperm production?
<37°C
What are the three mechanisms for regulating testicular temperature?
- Cremaster muscle
- Dartos muscle
- Pampiniform venous plexus
What is the tunica albuginea?
The capsule that surrounds each testis
What do interstitial cells (Leydig cells) produce?
Androgens, primarily testosterone
What is spermatogenesis?
The process of sperm formation
What is the outcome of meiosis during spermatogenesis?
Four haploid daughter cells (gametes)
What is spermiogenesis?
The process of maturation of spermatids into sperm
What forms the blood-testis barrier?
Tight junctions between adjacent Sertoli cells
What is the rete testis?
A network where sperm partially mature
What is the duct system in the male reproductive system?
- Epididymis
- Ductus (vas) deferens
- Ejaculatory duct
- Urethra
What is the primary function of the epididymis?
Temporary storage site for immature sperm
What is a vasectomy?
Removal of a 1 cm segment of the vas deferens as a form of birth control
What are the regions of the urethra?
- Prostatic urethra
- Membranous urethra
- Spongy (penile) urethra
What do seminal vesicles produce?
A thick, yellowish secretion that contains fructose, vitamin C, and prostaglandins
What is the function of the prostate gland?
Secretes a milky fluid that helps to activate sperm
What do bulbourethral glands produce?
Thick, clear mucus that cleanses the urethra and serves as a lubricant
What is the composition of semen?
- 60% seminal vesicle fluid
- 30% prostatic fluid
- 10% sperm and spermatic duct secretions
What is a normal sperm count per milliliter of semen?
50-120 million sperm/ml
What are the normal pH levels for semen?
7.2 to 8.0 pH
What is erectile dysfunction (ED)?
Inability to attain an erection
What hormone stimulates reproductive organ development in males?
Testosterone
What happens to the hypothalamus’s sensitivity to androgens at puberty?
It becomes less sensitive, increasing GnRH secretion
What does Viagra® and similar drugs enhance?
The release of NO
What happens to the hypothalamus at puberty regarding androgens?
Becomes less sensitive to inhibitory effect of androgens
What does increased GnRH secretion lead to?
Increased FSH and LH release
What is the most important hormonal product of the testes?
Testosterone
List the effects of testosterone.
- Stimulates reproductive organ development
- Underlies sex drive
- Causes secondary sex characteristics (deepening of voice, increased hair growth, enlargement of skeletal muscles, increased bone growth and density)
What hormone does the hypothalamus release?
Gonadotropin-releasing hormone (GnRH)
What do FSH and LH stimulate in the male reproductive system?
- FSH stimulates spermatogenesis
- LH stimulates testosterone release
What role does inhibin play in male reproductive hormone regulation?
Reduces FSH secretion and sperm production
What are the primary sex organs in males and females?
- Males: Testes
- Females: Ovaries
What are the gametes produced by males and females?
- Males: Sperm
- Females: Ova
What hormones are associated with male and female reproductive systems?
- Males: Testosterone
- Females: Oestrogen and Progesterone
What structures support the ovaries?
- Suspensory ligaments
- Ovarian ligaments
- Broad ligaments
At what stage does a female’s reproductive ability begin?
At puberty with the onset of the menstrual cycle
What are primary oocytes and when are they arrested?
Meiosis arrested in late prophase I
What is the difference between pre-granulosa and granulosa cells?
Pre-granulosa has one cell layer; granulosa has multiple cell layers
What are the phases of the ovarian cycle?
- Follicular phase
- Luteal phase
What occurs during the follicular phase of the ovarian cycle?
Vesicular follicles begin to secrete increasing amounts of oestrogens
What is the function of the uterine tubes?
Receive the ovulated oocyte and provide a site for fertilization
What are the three regions of the uterus?
- Body
- Fundus
- Cervix
What are the risk factors for cervical cancer?
- Smoker
- Early sexual activity
- STIs
- Cervical inflammation
What is the purpose of a cervical smear?
To detect abnormal cells and early signs of cervical cancer
What is the inner layer of the uterus called?
Endometrium
What happens if the egg is fertilized?
HCG prevents degeneration of the corpus luteum
What is the external genitalia of females referred to as?
Vulva
What changes occur in the female reproductive system at puberty?
- Promote oogenesis
- Enhance reproductive tract functionality
- Development of secondary sexual characteristics
What are mammary glands and their function?
Modified sweat glands that produce milk for newborns
What is mammography?
X-ray examination that detects breast cancers
What typically happens to the number of eggs as women reach menopause?
Only about 1000 eggs are left
What is the most-used contraceptive method?
Birth control pill
What is the function of the morning-after pill (MAP)?
Disrupts hormonal signals to prevent fertilization
What are secondary effects of hormonal changes?
Hot flushes, decrease in bone mass, gradually thinning skin, breasts begin to atrophy
These changes occur as a result of hormonal shifts, particularly during menopause.
What is the most-used contraceptive method?
Birth control pill
The pill provides a relatively constant supply of ovarian hormones.
What does the birth control pill prevent?
Maturation of ovarian follicles, ovulation, and reduces menstrual flow
This mimics the hormonal state of pregnancy.
What is the function of the morning-after pill (MAP)?
Disrupts normal hormonal signals to prevent fertilization
It must be taken within 3 days of unprotected intercourse.
What are some hormonal birth control devices?
- Minipill (tablet)
- Norplant (rods placed under the skin)
These methods work by altering hormonal balances to prevent ovulation.
What is an IUD?
Plastic or metal device inserted into the uterus
It prevents implantation of a fertilized egg.
What are the two types of sterilization methods mentioned?
- Tubal ligation (females)
- Vasectomy (males)
These methods involve cutting or cauterizing reproductive ducts.
What is coitus interruptus?
Withdrawal of penis prior to ejaculation
This method aims to prevent sperm from entering the vagina.
What is the rhythm method?
Avoiding intercourse during ovulation or fertility periods
It involves tracking basal temperature and cervical mucus changes.
Name some barrier methods of contraception.
- Diaphragms
- Cervical caps
- Condoms
- Spermicidal foams
- Gels
- Sponges
These methods physically block sperm from reaching the egg.
What is abortion?
Termination of pregnancy
This can be induced through various medical methods.
What is RU486?
Also known as the ‘abortion pill’, it induces miscarriage during the first 7 weeks of pregnancy
This medication alters hormonal levels to terminate a pregnancy.
What are the primary sex organs for males and females?
Testes for males; ovaries for females
These organs are responsible for gamete production.
Which structure is referred to as a ‘sperm factory’?
Seminiferous tubules
This is where sperm are produced in the testes.
What is the primary function of the epididymis?
Storage and maturation of sperm
It is essential for sperm development before ejaculation.
Where does fertilization typically occur?
The ampulla of the uterine tube
This is the site where sperm and oocyte meet.
What hormones influence changes in the endometrium?
Oestrogen and progesterone
These hormones regulate the menstrual cycle and prepare the uterus for potential implantation.
Which layer of the endometrium is shed during menstruation?
Functional layer
The basal layer remains intact to regenerate the functional layer.
What is the narrowing portion of the uterus just above the cervix called?
Isthmus
This area connects the body of the uterus to the cervix.
From where does the vagina extend?
Cervix to the body exterior
This structure serves as the canal for childbirth and menstrual flow.
Which external female genital structure is covered in pubic hair post-puberty?
Mons pubis
This fatty tissue protects the pubic symphysis.
Where is milk produced in lactating females?
Glandular alveoli
Milk is then transported through lactiferous ducts.
Which hormones are involved in the positive feedback mechanisms for milk production?
- Prolactin
- Oxytocin
These hormones stimulate milk production and ejection during breastfeeding.
